log/logd.c

   1 /*
   2  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License version 2.1
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <stdio.h>
  15 #include <unistd.h>
  16 #include <syslog.h>
  17 #include <unistd.h>
  18
  19 #include <linux/types.h>
  20
  21 #include <libubox/uloop.h>
  22 #include <libubox/blobmsg.h>
  23 #include <libubox/list.h>
  24 #include <libubox/ustream.h>
  25 #include <libubus.h>
  26
  27 #include "syslog.h"
  28
  29 int debug = 0;
  30 static struct blob_buf b;
  31 static struct ubus_auto_conn conn;
  32 static LIST_HEAD(clients);
  33
  34 enum {
  35         READ_LINES,
  36         READ_STREAM,
  37         __READ_MAX
  38 };
  39
  40 static const struct blobmsg_policy read_policy[__READ_MAX] = {
  41         [READ_LINES] = { .name = "lines", .type = BLOBMSG_TYPE_INT32 },
  42         [READ_STREAM] = { .name = "stream", .type = BLOBMSG_TYPE_BOOL },
  43 };
  44
  45 static const struct blobmsg_policy write_policy =
  46         { .name = "event", .type = BLOBMSG_TYPE_STRING };
  47
  48 struct client {
  49         struct list_head list;
  50
  51         struct ustream_fd s;
  52         int fd;
  53 };
  54
  55 static void
  56 client_close(struct ustream *s)
  57 {
  58         struct client *cl = container_of(s, struct client, s.stream);
  59
  60         list_del(&cl->list);
  61         ustream_free(s);
  62         close(cl->fd);
  63         free(cl);
  64 }
  65
  66 static void client_notify_state(struct ustream *s)
  67 {
  68         client_close(s);
  69 }
  70
  71 static void
  72 log_fill_msg(struct blob_buf *b, struct log_head *l)
  73 {
  74         blob_buf_init(b, 0);
  75         blobmsg_add_string(b, "msg", l->data);
  76         blobmsg_add_u32(b, "id", l->id);
  77         blobmsg_add_u32(b, "priority", l->priority);
  78         blobmsg_add_u32(b, "source", l->source);
  79         blobmsg_add_u64(b, "time", l->ts.tv_sec * 1000LL);
  80 }
  81
  82 static int
  83 read_log(struct ubus_context *ctx, struct ubus_object *obj,
  84                 struct ubus_request_data *req, const char *method,
  85                 struct blob_attr *msg)
  86 {
  87         struct client *cl;
  88         struct blob_attr *tb[__READ_MAX];
  89         struct log_head *l;
  90         int count = 0;
  91         int fds[2];
  92         int ret;
  93         bool stream = true;
  94
  95         if (!stream)
  96                 count = 100;
  97
  98         if (msg) {
  99                 blobmsg_parse(read_policy, __READ_MAX, tb, blob_data(msg), blob_len(msg));
 100                 if (tb[READ_LINES])
 101                         count = blobmsg_get_u32(tb[READ_LINES]);
 102                 if (tb[READ_STREAM])
 103                         stream = blobmsg_get_bool(tb[READ_STREAM]);
 104         }
 105
 106         if (pipe(fds) == -1) {
 107                 fprintf(stderr, "logd: failed to create pipe: %s\n", strerror(errno));
 108                 return -1;
 109         }
 110
 111         l = log_list(count, NULL);
 112         if (stream) {
 113                 ubus_request_set_fd(ctx, req, fds[0]);
 114                 cl = calloc(1, sizeof(*cl));
 115                 cl->s.stream.notify_state = client_notify_state;
 116                 cl->fd = fds[1];
 117                 ustream_fd_init(&cl->s, cl->fd);
 118                 list_add(&cl->list, &clients);
 119                 while ((!tb[READ_LINES] || count) && l) {
 120                         log_fill_msg(&b, l);
 121                         l = log_list(count, l);
 122                         ret = ustream_write(&cl->s.stream, (void *) b.head, blob_len(b.head) + sizeof(struct blob_attr), false);
 123                         if (ret < 0)
 124                                 break;
 125                 }
 126         } else {
 127                 while ((!tb[READ_LINES] || count) && l) {
 128                         log_fill_msg(&b, l);
 129                         ubus_send_reply(ctx, req, b.head);
 130                         l = log_list(count, l);
 131                 }
 132         }
 133         blob_buf_free(&b);
 134         return 0;
 135 }
 136
 137 static int
 138 write_log(struct ubus_context *ctx, struct ubus_object *obj,
 139                 struct ubus_request_data *req, const char *method,
 140                 struct blob_attr *msg)
 141 {
 142         struct blob_attr *tb;
 143         char *event;
 144
 145         if (msg) {
 146                 blobmsg_parse(&write_policy, 1, &tb, blob_data(msg), blob_len(msg));
 147                 if (tb) {
 148                         event = blobmsg_get_string(tb);
 149                         log_add(event, strlen(event) + 1, SOURCE_SYSLOG);
 150                 }
 151         }
 152
 153         return 0;
 154 }
 155
 156 static const struct ubus_method log_methods[] = {
 157         UBUS_METHOD("read", read_log, read_policy),
 158         { .name = "write", .handler = write_log, .policy = &write_policy, .n_policy = 1 },
 159 };
 160
 161 static struct ubus_object_type log_object_type =
 162         UBUS_OBJECT_TYPE("log", log_methods);
 163
 164 static struct ubus_object log_object = {
 165         .name = "log",
 166         .type = &log_object_type,
 167         .methods = log_methods,
 168         .n_methods = ARRAY_SIZE(log_methods),
 169 };
 170
 171 void
 172 ubus_notify_log(struct log_head *l)
 173 {
 174         struct client *c;
 175
 176         if (list_empty(&clients))
 177                 return;
 178
 179         blob_buf_init(&b, 0);
 180         blobmsg_add_string(&b, "msg", l->data);
 181         blobmsg_add_u32(&b, "id", l->id);
 182         blobmsg_add_u32(&b, "priority", l->priority);
 183         blobmsg_add_u32(&b, "source", l->source);
 184         blobmsg_add_u64(&b, "time", (((__u64) l->ts.tv_sec) * 1000) + (l->ts.tv_nsec / 1000000));
 185
 186         list_for_each_entry(c, &clients, list)
 187                 ustream_write(&c->s.stream, (void *) b.head, blob_len(b.head) + sizeof(struct blob_attr), false);
 188
 189         blob_buf_free(&b);
 190 }
 191
 192 static void
 193 ubus_connect_handler(struct ubus_context *ctx)
 194 {
 195         int ret;
 196
 197         ret = ubus_add_object(ctx, &log_object);
 198         if (ret) {
 199                 fprintf(stderr, "Failed to add object: %s\n", ubus_strerror(ret));
 200                 exit(1);
 201         }
 202         fprintf(stderr, "log: connected to ubus\n");
 203 }
 204
 205 int
 206 main(int argc, char **argv)
 207 {
 208         int ch, log_size = 16;
 209
 210         signal(SIGPIPE, SIG_IGN);
 211         while ((ch = getopt(argc, argv, "S:")) != -1) {
 212                 switch (ch) {
 213                 case 'S':
 214                         log_size = atoi(optarg);
 215                         if (log_size < 1)
 216                                 log_size = 16;
 217                         break;
 218                 }
 219         }
 220         log_size *= 1024;
 221
 222         uloop_init();
 223         log_init(log_size);
 224         conn.cb = ubus_connect_handler;
 225         ubus_auto_connect(&conn);
 226         uloop_run();
 227         log_shutdown();
 228         uloop_done();
 229         ubus_auto_shutdown(&conn);
 230
 231         return 0;
 232 }